This invention relates to a dispenser for measuring and dispensing a metered amount of a product, and more particularly, to a dispenser adapted for attachment to a squeeze tube for dispensing a metered amount of a viscous or semi-fluid material.
The present invention is especially useful in measuring metered amounts of ointments, or other medications used by physicians in treating their patients. A typical need for the present invention is in measuring a specific amount of ointment used in treating a patient's eye after eye surgery. In the past, physicians have used liquid or other free-flowing medications for treating a patient's eye. The medicinal portion of such a liquid solution is diluted and often becomes lost in the patient's eye due to the free-floating characteristic of the liquid. As a result, the physician often has difficulty in precisely controlling the amount of medication which actually comes in contact with the particular portion of the eye being treated. In response to this problem, medication for treating the eye has recently been produced as an ointment in which the medicinal portion is greatly concentrated when compared with liquid medications. The present invention provides a dispenser for measuring and dispensing such highly concentrated medications in extremely accurate dosages.
The dispenser of this invention can be used for home application of ointments by the patient. The dispenser is adapted for attachment to a squeeze tube containing the ointment. The dispenser includes a rotatable valve member having a passage with a slidable piston for controlling the amount of ointment dispensed by the patient. In response to pressure applied to the squeeze tube, the piston slides in the passage in the valve member to dispense a metered amount of ointment. The fixed size of the piston ensures that the patient will dispense the required dosage each time. The physician simply selects the particular dispenser configuration that will dispense the required dosage. After the ointment is dispensed the valve member is rotated to re-position the piston for the next dispensing cycle. Inasmuch as the dispenser can be used for self-treatment by a patient, it is desirable that the rotatable valve member be non-removably sealed in the dispenser body so the physician can be confident that the dispenser cannot be taken apart and the fixed dosage tampered with and that the ointment will remain sterile throughout its use.